Can opener



June 26, 1956 J. T. HELLYER CAN OPENER Filed Nov. 5, 1955' INVENTOR JOHN T HELL YER ATTORNEYS.

CAN OPENER John T. Hellyer, Geneva, 11]., assignor to The D;azey Cor poration, St. Louis, M0,, a corporation of Missouri Application November 3, 1955, Serial No. 544,716

8 Claims. (Cl. ML-8.5)

This invention relates to improvements in can openers, and has particular reference to can openers of the type characterized by a slotted opening in the base or frame, which opening serves to guide a feeding wheel in its movement toward and from a cutting element. Rotation of a crank in one direction causes the feeding wheel to travel to an operating position at one end of the guide slot. Rotation of the crank in the opposite direction moves the feeding wheel away from the cutting element to permit removal of the opened can, and to condition the device for insertion of another can.

This type of opener has a number of distinct advantages, among which are simplicity of operation and economy of manufacture. Such openers, however, as heretofore constructed, have not operated satisfactorily on cans of all sizes and shapes, or on those having relatively thick side scams or irregularities in their rims. A further fault is the tendency for such openers to drop cans during the cutting process.

The object of the present invention is to improve the efficiency and operating characteristics of can openers of the type described. This object is achieved by provisions in connection with the feeding wheel assembly which enable the opener to function more smoothly and positively on cans of various sizes and shapes as well as on cans which have irregularities in their rim portions.

Another object is to extend the useful life of this type of opener.

A particular object is achieved by the provision of means which afford controlled axial and angular yieldability of the feeding wheel during the cutting operation, and such that the feeding wheel is enabled to adjust itself to thickened or deformed portions while retaining an operating grip on the can rim. The improvements described herein afford smoothness and ease of operation, and reliability that is to be found only in complex, more costly can openers.

These and other objects and advantages will appear from the following description of a practical embodiment of my invention and to the drawing wherein:

Fig. l is a fragmentary side elevational view showing the operating parts of the opener in initial or preliminary positions;

Fig. 2 is a fragmentary elevational view showing the opposite side of the can opener, with the' part's thereof in the same relative positions as shown in Fig. 1;

Fig. 3 is a sectional view taken at line 3-3 of Fig. 1;

Fig. 4 is a fragmentary sectional view taken on line 44 of Fig. 2;

Fig. 5 is a side elevational view, similar to Fig. l but with the operating parts of the opener shown in their normal operating positions;

Fig. 6 is a side clevational view, similar to Fig. 2, with the operating parts shown in their operating posi tions, and

Figs. 7 and 8 are plan and side views of a preferred type of annular compression spring, employed in the assembly.

uited rates Fatent O i 2,751,679 Patented June 26, 1956 Referring now by characters of reference to the drawing, 10 designates the base plate or frame member of the opener. This member, consisting of a ilat, elongated metal plate, is provided at one end with suitable means for mounting the unit on a wall or other support, represented in the present example by the bracket part 11. The operating elements of the opener are located at the outer or forward end of the base 16 and these include a cutting element 12, shown herein to be a disc having front and rear side surfaces that taper to a sharp cutting edge 13, and a rearwardly extended integral hub portion 14. Disc 12 is rotatably mounted on astub shaft constituted by the machine screw 15 which is disposed with its axis inclined downwardly with respect to the plane of the base plate 10. The threaded end 16 of screw 15 passes through an opening formed in the sloping front face of the boss 17, formed on base 10, and is secured to the said boss by a nut 18, all as best appears in Fig. 3.

Also projecting from the front side of the base 10 are a pair of studs 19 and 20 which are arranged to have their under surface portions engaged by the top rim of the can during the opening process as appears from Fig. 5. The stud 19 is cylindrical and is located inwardly or rearwardly of the cutting. disc and at an elevation such that its lower can contacting surface, indicated at 21, is at, or slightly above the level of the cen ter of the cutting disc 12. The companion stud 20' is located forwardly or outwardly from the cutting disc and this member presents a can-engaging surface 22 which is located at or slightly below the center of the cutting disc. The described studs tend to hold the can in a position such that its top is slightly inclined as shown. Stud 20 is further characterized by a relatively enlarged frustoconical base portion 23, which presents a sloping shoulder that normally is engaged by the can rim during the initial or puncturing stage of the opening process. As the can is raised by the upward movement of the feeding wheel during the initial or puncturing stage the said sloping shoulder imparts an outward thrust on that portion of the can rim which is ahead of the cutter. These provisions hold the can in a position with respect to the cutting and feeding wheels which conduces to smooth, positive and clean cutting action by those members.

Below the cutting disc 12 the base plate 10 is provided with an offset portion indicated at 25 (Fig. 3), that forms a shallow recess or cavity 10a in the front side, and a protuberance on the rear side of the base. Mounted within the said recess is an annular, relatively flat compression spring 26, which is adapted to press outwardly against a thrust plate 27, the outer surface thereof being approximately flush with the front surface of the base plate. Plate 27 is appreciably larger than the feeding wheel 28 which it bears outwardly against, as will be hereinafter described. The compression spring 26 consisting of a resilient wave washer also is considerably larger than the feeding wheel 28 with respect to its internal as well as its external diameters. Member 26 is held within the base recess and is prevented from shifting laterally out of its normal location directly below the cutting disc by its confinement between the arcuate shoulder 29 that forms the upper side of the recess and a lip 30 that projects forwardly from the lower edge of the base plate. Thrust plate 27 is capable of moving in slight degree toward and from the base, and also of rocking to a limited angular extent. All such movement is attended by a yielding of the spring washer 2'6 and is opposed by that member. Lateral movement of the thrust plate 27 islimited by projections 31 formed on base 10 adjacent opposite side margins of the base recess. These projections are formed, in the present example, by perforating and bending the metal of the base. The thrust plate 27 is prevented from moving vertically,

being confined between the shoulders 29 at its upper edge, and by the lip 30 at its lower edge.

On the rear side of the base there is provided a thin sheet metal wear plate 32, preferably of stainless steel. This member is fixedly secured to the face of the said protuberance, being fastened in place by a short stud 33 whose outer end is flush with the outer surface of the wear plate 32. Also serving to fasten the wear plate 32 is a pin 34 on which is journalled a roller bearing 35, which bearing coacts with a cam member to be hereinafter designated and described.

The thrust and wear plates 27 and 32 and the intervening portion 25 of the base plate are provided with mutually registering arcuate slots, the common opening 36 thus produced constituting a guide-way for the feeding wheel assembly in its travel between the limit positions thereof, shown in Figs. 1 and 5. The guide slot 36 receives the neck portion 37 of the feeding wheel hub, this neck portion fitting the slot with a minimum of lateral play. As best appears from Fig. 3 the feeding wheel hub is of stepped diameter and includes a collar portion 38 which maintains the feeding wheel 23 spaced from the face of the thrust plate 27 and presents a shoulder which bears against the thrust plate at the border of the guide slot. A reduced rear extremity 39 of the said hub has a cam 40 and the hub 41 of a crank 42 mounted thereon and secured thereto by a rivet 43, the said feeding wheel, cam and crank being effectively locked together for rotation as a unit by the interengagement of the flat surface portion indicated at 44, Fig. 2.

Cam 40 has an outer edge of generally spiral trend which rides upon the roller bearing 35. Since the location of bearing 35 is fixed, rotation of the cam causes its center to shift. The relative arrangement of the cam, bearing and arcuate slot 36 is such as to cause the cam center and its concentric feeding wheel 28 to shift upwardly along the guide slot when the feeding wheel and parts assembled thereto are turned in a clockwise direction (Fig. 2). It will be understood that a cam whose rim or flange is rested upon the toothed edge of the feeding wheel will be raised by the means above described and its top wall thusly forced against the sharp edge of the cutter element will become punctured by the said cutter. Continued turning of the crank in the same direction revolves the can and causes its top wall to be severed by the cutter. Thereafter the can may be removed from the opener by reversing the crank a fraction of a turn which allows the feeding wheel to drop away from the cutting wheel.

Noteworthy is the particular arrangement and relationship of the positioning studs 19 and Ztl, the cutting wheel 12 and the guide slot 36. It is desirable to have the feeding wheel 28 situated a slight distance over center, when in its normal operating position, which means that the guide slot 36 is such as to permit the feeding wheel to advance from an inactive position at one side of a substantially vertical plane through the feeding wheel shaft (the left side, Fig. 4), through such plane and to a final operating position at the opposite side thereof.

The unique mounting arrangement of the feeding wheel assembly conduces in large part to the superior operating characteristics of the present can opener. It will be understood that the spring washer 26 exerts an outward force on the plate 27, which force is transmitted therethrough to the feeding wheel. The feeding wheel is movable inwardly as for example under the influence of a thick seam or irregularity in the can, but such yielding of the feed wheel is opposed by the spring washer 26. The spring washer and thrust plate, while tending to hold the feeding wheel in a normal position parallel to the base plate permits the feeding wheel to yield angularly and to adjust and adapt itself to bends, corners or irregularities in adjacent portions of the can. Notable is the relatively large and substantially flat spring 26 which controls the yieldability of the feeding wheel. This compression spring exerts its force on the thrust plate near the outer margins of that member. A portion of the spring follows the curve of the outer edge of the guide slot 36 (Fig. 5), and bears directly against that portion of the thrust plate which engages the feeding wheel.

Having described my invention, what I claim and desire to secure by Letters Patent is:

1. In a can opener, a base, a cutting member mounted on said base, a yieldable thrust plate mounted in a relatively fixed location on said base, said thrust plate having a guide slot formed therein, a feeding wheel movable along said guide slot toward and away from said cutting member, said thrust plate bearing axially against the feeding wheel, and means for rotating said feeding wheel and for moving the same toward and from the cutting member.

2. in a can opener, a base, a cutting element and a feeding wheel mounted on the base, means for moving said feed wheel toward and from the cutting element, a thrust plate between said feeding wheel and said base, mutually registering guide slots in said base and thrust plate, a shaft for said feeding wheel extending through said slots, and a spring acting on said thrust plate to apply an axially outward force on said feeding wheel.

3. In a can opener, a base, a cutting element, a feeding wheel mounted on said base for movement toward and away from the said cutting element, a yieldable thrust plate between the base and feeding wheel, mutually reg istering guide slots formed in said base and thrust plate, a shaft for said feeding wheel extending through said guide slot, means for rotating said shaft and shifting the position thereof along said guide slots, and spring means acting on said thrust plate axially toward said feeding wheel.

4. A can opener as set forth in claim 3 wherein the said spring means comprises an annular compression spring which encircles the feeding wheel shaft between the base and thrust plate.

5. A can opener as set forth in claim 3 wherein the said spring means comprises a substantially fiat annular compression spring encircling the feeding Wheel between the base and thrust plate, said spring being of internal diameter appreciably greater than the diameter of the feeding wheel shaft, and means on said base holding said spring in a substantially fixed position relative thereto.

6. A can opener as set forth in claim 3 wherein the said spring means comprises a substantially fiat annular compression spring of internal diametcr appreciably greater than the diameter of the feeding wheel shaft. said spring being disposed between the thrust plate and base member and acting outwardly on said thrust plate adjacent marginal portions of said guide slot, and means on said base for preventing substantial, lateral displace ment of said spring.

7. In a can opener, a base having a shallow cavity, a cutting element mounted on the base adjacent said cavity, a yieldable thrust plate fitting within said cavity, said base and thrust plate having mutually registering guide slots, a shaft extending transversely through said guide slots and displaceable therein toward and away from said cutting element, a feeding wheel on said shaft, means for turning and displacing said shaft, a flat annular compression spring encircling said shaft, means holding said spring in a relatively fixed position between said base and thrust plate, said spring bearing outwardly against marginal portions of said thrust plate.

8. In a can opener, a flat base having a shallow cavity formed in one side thereof, a rotatable cutting disc mounted on the base above said cavity, a yieldable thrust plate mounted in said cavity, projections on the base engaging said plate and holding the same against substantial edgewise movement, said base and thrust plate having mutually registering, arcuate guide slots, a flat annular compression spring disposed between the base and thrust 6 plate, said spring bearing outwardly against marginal por- References Cited in the file of this patent tions of the thrust plate, a rotor assembly including a UNITED STATES PATENTS shaft having fixed thereon a feeding wheel adjacent the 2 244 846 Moener June 10 1941 thrust plate, a cam and a crank, and a fixed bearlng ele- 2,573,031 La Forte Oct 1951 ment coacting with said cam, said shaft extending through 5 and being movable along said guide slots by the action of the cam on said bearing element. 

